KR102316170B1 - Electrode protection using a composite comprising an electrolyte-inhibiting ion conductor - Google Patents

Abstract

Composite structures comprising an ion-conducting material and a polymeric material (eg, a separator) for protecting an electrode are generally described. The ion-conducting material may be in the form of a layer bonded to the polymer separator. The ion-conducting material may include lithium oxysulfide having a lithium-ion conductivity of ^{at least 10 −6 S/cm.}

Description

ELECTRODE PROTECTION USING A COMPOSITE COMPRISING AN ELECTROLYTE-INHIBITING ION CONDUCTOR

Composite structures comprising an ion-conducting material and a polymeric material (eg, a separator) for protecting an electrode are generally described.

Rechargeable primary electrochemical cells often include one or more protective layers to protect the electroactive surface. Depending on the specific protective layer(s), the protective layer(s) isolates the underlying electroactive surface from interaction with the electrolyte and/or other components in the electrochemical cell. In order to provide adequate protection of the lower electrode, it is preferred that the protective layer(s) continuously cover the lower electrode and exhibit a minimum number of defects. While techniques exist for forming the protective layer(s), methods that allow the formation of the protective layer(s) that improve the performance of the electrochemical cell are advantageous.

Composite structures comprising an ion-conducting material and a polymeric material (eg, a separator) for protecting an electrode are generally described. Related systems and methods are generally described. The ion-conducting material can inhibit the interaction between the protected electrode and the electrolyte.

In one set of embodiments, an electrochemical cell is described. An electrochemical cell can include, for example, a first electrode comprising lithium as the electroactive material, a second electrode, and a composite positioned between the first and second electrodes. The composite includes a separator comprising pores having an average pore size and having a ^{bulk electronic resistivity of at least about 10 4} Ohm-meters, and an ionic conductor layer coupled to the separator. The ion conductor layer has a lithium-ion conductivity ^{of at least 10 −6 S/cm.} said ion conductor layer comprises lithium oxysulfide having an oxide content of 0.1 to 20 wt. %, and/or said ion conductor layer contains oxygen atoms to sulfur atoms (O:S) atoms in the range of 0.001:1 to 1.5:1. lithium oxysulfide having a ratio.

In one set of embodiments, an electrochemical cell is described. An electrochemical cell can include, for example, a first electrode comprising lithium as the electroactive material, a second electrode, and a composite positioned between the first and second electrodes. The composite includes a separator comprising pores having an average pore size and having a ^{bulk electronic resistivity of at least about 10 4} Ohm-meters, and an ionic conductor layer coupled to the separator. The ion conductor layer has a lithium-ion conductivity ^{of at least 10 −6 S/cm.} The ion conductor layer comprises lithium oxysulfide having an oxide content of 0.1 to 20 wt. %, and/or the ion conductor layer contains an atom of sulfur to oxygen (S:O) in the range of 0.5:1 to 1000:1. lithium oxysulfide having a ratio.

An electrochemical cell can include, for example, a first electrode comprising lithium as the electroactive material, a second electrode, and a composite positioned between the first and second electrodes. The composite includes a separator comprising pores having an average pore size and having a ^{bulk electronic resistivity of at least about 10 4} Ohm-meters, and an ionic conductor layer coupled to the separator. The ion conductor layer has a lithium-ion conductivity ^{of at least 10 −6 S/cm.} The ion conductor layer comprises an atomic ratio of sulfur:oxygen from 1:1 to 100:1.

An electrochemical cell can include, for example, a first electrode comprising lithium as the electroactive material, a second electrode, and a composite positioned between the first and second electrodes. The composite includes a separator comprising pores having an average pore size and having a ^{bulk electronic resistivity of at least about 10 4} Ohm-meters, and an ionic conductor layer coupled to the separator. The ion conductor layer has a lithium-ion conductivity ^{of at least 10 −6 S/cm.} The ion conductor layer comprises lithium oxysulfide having an atomic ratio of oxygen atoms to sulfur atoms (O:S) in the range of 0.001:1 to 1.5:1, such as 0.01:1 to 0.25:1.

The electrochemical cell (preferably the electrochemical cell described above) in which the electrochemical cell is a lithium-sulfur cell includes, for example, a first electrode comprising lithium, a second electrode comprising sulfur, the first electrode and the a separator arranged between the second electrode, and a solid ionic conductor contacting and/or bonded to the separator, wherein the solid ionic conductor comprises a lithium-ion conductive oxysulfide.

In some embodiments of the electrochemical cells described herein, the ionic conductor layer comprising lithium oxysulfide is part of a multilayered structure comprising more than one ion conductor layer. In some examples, two or more layers of the multilayered structure are formed of different materials. In another example, two or more layers of the multilayered structure are formed of the same material. The ion conductor layer comprising lithium oxysulfide may be in direct contact with each of the first electrode and the separator.

In some embodiments of the electrochemical cells described herein, the separator has a thickness of between 5 microns and 40 microns. The separator may have a bulk electronic resistivity ^{of 10 10} Ohm meters or greater, such as 10 ¹⁰ Ohm meters to 10 ^{15 Ohm meters or greater.}

In some embodiments of the electrochemical cells described herein, the separator is a solid polymer separator. In some cases, the separator is a solid comprising a mixture of a polymeric binder and a filler comprising a ceramic or glassy/ceramic material. In certain embodiments, the separator is poly(n-pentene-2), polypropylene, polytetrafluoroethylene, polyamide (such as polyamide (nylon), poly(ε-caprolactam) (nylon 6), poly (hexamethylene adipamide) (nylon 66)), polyimides (such as polynitrile, and poly(pyromelitimide-1,4-diphenyl ether) (Kapton®) (Nomex) (NOMEX®) (KEVLAR®)), polyether ether ketone (PEEK), and combinations thereof.

In some embodiments of the electrochemical cells described herein, the composite is formed by treating the surface of the separator with a plasma prior to depositing an ion conductor layer on the surface of the separator.

In some embodiments of the electrochemical cells described herein, the lithium oxysulfide has the formula x(yLi ₂ S+zLi ₂ O)+MS ₂ , wherein M is Si, Ge, or Sn, wherein y+z=1, and x may be 0.5 to 3.

In some embodiments of the electrochemical cells described herein, the ion conductor layer comprises 0% to 30% by weight of the glass forming additive of the inorganic ion conductor material.

In some embodiments of the electrochemical cells described herein, the ion conductor layer comprises one or more lithium salts. Lithium salts may include, for example, LiI, LiBr, LiCl, Li ₂ CO ₃ , and/or Li ₂ SO ₄ . One or more lithium salts may be added to the inorganic ion conductor material, for example, from 0 to 50 mole %.

In some embodiments of the electrochemical cells described herein, the separator has an average pore size of 5 microns or less, 1 micron or less, 0.5 microns or less, 0.05-5 microns, or 0.1-0.3 microns.

In some embodiments of the electrochemical cells described herein, the ion conductor layer has a thickness of 2 microns or less, 1.5 microns or less, 1 micron or less, 800 nm or less, 600 nm or less, or 400 nm to 600 nm.

In some embodiments of the electrochemical cells described herein, the composite has a lithium ion conductivity at ^{25°C of at least 10 −5} S/cm, at least 10 ⁻⁴ S/cm, or at least 10 ^{−3 S/cm.}

In some embodiments of the electrochemical cells described herein, the ratio of the thickness of the ion conductor layer to the average pore size of the separator is at least 1.1:1, at least 2:1, at least 3:1, or at least 5:1.

In some embodiments of the electrochemical cells described herein, the adhesive strength between the separator and the ion conductor layer is at least 350 N/m or at least 500 N/m. In some instances, the adhesive strength between the separator and the ion conductor layer passes the tape test according to standard ASTM D3359-02.

In some embodiments of the electrochemical cells described herein, the first electroactive material comprises lithium, eg, the first electroactive material may comprise lithium metal and/or a lithium alloy. In some cases, the second electrode comprises sulfur as the second electroactive material.

In some embodiments of the electrochemical cells described herein, the ion conductor is deposited on the separator by an electron beam evaporation method or a sputtering process.

In one set of embodiments, an electrochemical cell described herein comprises a first electrode comprising lithium, a second electrode comprising sulfur, a separator arranged between the first electrode and the second electrode, and the separator disposed therebetween. A lithium-sulfur battery comprising a contacted and/or bonded solid ionic conductor, the solid ionic conductor comprising a lithium-ion conductive oxysulfide.

In some embodiments of the electrochemical cells described herein, the solid ionic conductor comprises lithium oxysulfide.

In some embodiments of the electrochemical cells described herein, the solid ionic conductor has an atomic ratio of oxygen atoms to sulfur atoms (O:S) in the range of 0.001:1 to 1.5:1, such as 0.01:1 to 0.25:1. lithium oxysulfide with

In some embodiments of the electrochemical cells described herein, the solid ionic conductor is in the form of a layer having a thickness in the range of 1 nm to 7 microns.

In some embodiments of the electrochemical cells described herein, the separator is ionically conductive, wherein the average ionic conductivity of the separator is preferably at least 10 ^-7 S/cm at 25°C.

In some embodiments of the electrochemical cells described herein, the separator, and a solid ionic conductor in contact with the separator, constitute a composite, wherein the composite preferably has a thickness of from 5 microns to 40 microns. The composite may, in some embodiments, be a free-standing construct.

In some embodiments of the electrochemical cells described herein, the adhesive strength between the separator and the solid ionic conductor in contact with the separator is at least 350 N/m.

In some embodiments of the electrochemical cells described herein, said solid ionic conductor is positioned relative to one of said first and second electrodes. The solid ionic conductor may be arranged to inhibit interaction of the electrolyte present in the electrochemical cell with the electrode on which the solid ionic conductor is located.

In some embodiments of the electrochemical cells described herein, the solid ionic conductor comprises an amorphous lithium-ion conductive oxysulfide, a crystalline lithium-ion conductive oxysulfide, or an amorphous lithium-ion conductive oxysulfide and a crystalline lithium-ion conductive oxysulfide. mixtures of, for example, amorphous lithium oxysulfide, crystalline lithium oxysulfide, or mixtures of amorphous lithium oxysulfide and crystalline lithium oxysulfide.

In some embodiments of the electrochemical cells described herein, the present invention may be arranged between a first electrode and a second electrode, such as for separating a first electrode and a second electrode of an electrochemical cell in a lithium sulfur cell. To the use of a composite comprising: a separator, and a solid ionic conductor in contact with and/or bonded to the separator, wherein the solid ionic conductor comprises lithium-ion conductive oxysulfide. The solid ionic conductor may be arranged to inhibit interaction of an electrolyte present in the electrochemical cell with one of the electrodes of the electrochemical cell.

In some embodiments of the electrochemical cells described herein, the composite consists of a separator and a solid ionic conductor contacting and/or bonded to the separator, wherein the solid ionic conductor comprises a lithium-ion conductive oxysulfide. do.

In some embodiments of the electrochemical cells described herein, the present invention also relates to the steps of making or providing a separator, contacting and/or bonding a solid ionic conductor to said separator, further components of the electrochemical cell ( building element) and assembling the electrochemical cell.

In some embodiments of the electrochemical cells described herein, contacting and/or bonding a solid ionic conductor to the separator is accomplished by depositing an ionic conductor material on the separator surface. In some embodiments of the electrochemical cells described herein, the intermediate product obtained by contacting and/or bonding a solid ionic conductor to the separator is a composite that is a free-standing structure.

Specific features of aspects of the above-defined embodiments are hereinafter illustrated and discussed in greater detail herein.

Other advantages and novel features of the present invention will become apparent from the following detailed description of non-limiting embodiments of the invention when considered in conjunction with the accompanying drawings. In the event of conflicting and/or inconsistent disclosures between this specification and documents incorporated herein by reference, this specification shall control.

BRIEF DESCRIPTION OF THE DRAWINGS Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, which are schematic and are not intended to be drawn to scale. In the drawings, each identical or nearly identical component illustrated is typically represented by a single number. In the interest of clarity, not all components are labeled in all drawings, nor are all components of each embodiment of the invention not shown, for which illustration is not essential to one of ordinary skill in the art to understand the invention. From the drawing:
1 is an exemplary schematic diagram of an electrochemical cell comprising a composite structure comprising an ion conductor layer and a separator layer, according to a set of embodiments.
2 is an exemplary schematic diagram of a freestanding separator film comprising a tortuous hole path, in accordance with some embodiments.
3 is an exemplary schematic diagram of a porous separator coated with an ion conductor layer, in accordance with some embodiments.
4A, 4B, and 4C are exemplary scanning electron microscope (SEM) images of a ceramic coating deposited on a commercial separator.
5 is a plot of air permeation time versus inorganic ion conductor thickness for various inorganic ion conductor-separator composites.

To protect the electrode, a composite structure comprising an ion-conducting material and a polymeric material (eg, a separator) is generally described. The ion-conducting material may be in the form of a layer bonded to the polymer separator. The ion-conducting material may include lithium oxysulfide having a lithium-ion conductivity of ^{at least 10 −6 S/cm.}

Layers of ceramics or other inorganic protective materials (eg, glass, vitreous-ceramics) have been used to protect electrodes (eg, lithium anodes) from harmful interactions with electrolyte materials during operation of electrochemical cells. For example, protected lithium anode (PLA) structures comprising alternating successive layers of ionically conductive ceramic and ionically conductive polymer have been used. In certain cases, such a protective electrode structure may be ineffective. For example, the brittleness of the ceramic, defects within the ceramic membrane, and/or swelling exhibited by the polymer upon exposure to electrolyte may cause the protective electrode structure to crack or fail. . The cascading loss of these layers may result from internal defects in the ceramic, which may exist from handling and/or processing. This then allows the electrolyte to permeate into the polymer layer and swell. The expansion of this layer breaks the underlying ceramic layer, allowing the electrolyte to penetrate further and expand more of the polymer layer. Ultimately this can destroy all the protected layers, which can lead to the loss of the electrochemical cell.

One way to address the issues discussed above is to develop materials and/or structures that do not substantially expand or break. However, this can be a challenge. For example, many known polymers that are ionically conductive swell significantly in various electrochemical cell electrolytes. Also, it can be difficult to process ceramic materials so that they do not contain defects, and handling of such materials without the occurrence of defects (eg cracks) is difficult. The ceramic material should also have sufficient ionic conductivity so as not to inhibit ionic conduction across the protective layer(s).

One method described herein, which may be used to address the aforementioned issues with regard to ineffective electrode protection structures, is in the form of a separator with one or more ion conductor (eg, ceramic) layers that inhibit electrolyte interaction with the electrode. structures that allow the use of flexible low-expansion polymers that may be One or more of the ion conductor layer(s) may comprise a lithium oxysulfide material that provides sufficient ionic conduction across the composites detailed herein.

The separator may act as a smooth substrate upon which a smooth, thin layer of ion conductor may be deposited. Prior to deposition of the ion conductor layer, the separator surface may be treated to enhance its surface energy. The increased surface energy of the separator can improve adhesion (eg, bonding) between the ion conductor layer and the separator as compared to when the separator surface is untreated, as described below. As a result of the increased adhesion between the layers, the possibility of delamination of the layers can be reduced, and the mechanical stability of the ion conductor layer can be improved during cycling of the cell. Further, both the separator and the ion conductor layer can be included in the electrochemical cell, and the ion conductor layer does not need to be released from the substrate. Avoiding release of the ion conductor layer may, in some cases, improve the mechanical integrity of the ion conductor layer. In certain embodiments, the resulting ion conductor layer-separator composite may enhance the ability of the ion conductor layer to resist the mechanical stress it encounters when placed in a cell that is pressed against a rough cathode.

Further, in certain structures involving the use of flexible separator materials, the structures can inhibit mechanical loss of other negative mechanical effects, such as plastic deformation, when dimensional changes are introduced into the structure, such as through expansion. The separator material may or may not be ionically conductive, which may allow the use of a variety of separator materials (eg, polymers that either expand or do not expand upon exposure to electrolyte). Adoption of a design with this spatial orientation of ion conductors and separators may remove restrictions on the materials used, which may enable the use of materials that already exist. Other advantages are described in more detail below.

1 is an exemplary schematic cross-sectional view of an electrochemical cell including a separator and an ion conductor in the form of a composite structure according to a set of embodiments. 1 , the electrochemical cell 101 includes a first electrode 102 and a second electrode 104 . The first electrode 102 (and/or the second electrode 104 ) comprises an electroactive material. In certain embodiments, the electroactive material in the first electrode 102 comprises lithium. The first electrode 102 may be a negative electrode, and the second electrode 104 may be a positive electrode.

In the exemplary embodiment of FIG. 1 , the electrochemical cell 101 includes a separator 106 between the first electrode 102 and the second electrode 104 . Separator 106 may include pores 108 in which electrolyte may be present. The separator and ion conductor 112 form a composite structure, which can be bonded together as described herein to inhibit delamination or separation of the layers. The ionic conductor 112 may inhibit interaction of the electrolyte with the electroactive material inside the electrode 102 . In certain embodiments, the ionic conductor 112 substantially inhibits interaction of the electrolyte with the electroactive material inside the electrode 102 . Inhibiting or inhibiting the interaction of the electrolyte with the electroactive material inside the electrode 102 can reduce or eliminate the extent to which the electrode 102 is degraded or otherwise rendered inoperable by the electrolyte. Thus, in this way, the ion conductor 112 can function as a protective structure inside the electrochemical cell.

Although FIG. 1 depicts an electrochemical cell, it should be understood that in some embodiments not all components shown in the figure need to be present. For example, the articles and methods described herein may include only the components of an electrochemical cell (eg, a separator and an ionic conductor in the absence of one of the anode and/or cathode). It will also be understood that other components not shown in FIG. 1 may be included in the electrochemical cell in some embodiments. As one example, an ion conductor layer (eg, an inorganic layer ion conductor layer) can be part of a multilayered structure that includes more than one ion conductor layer. Two or more layers (eg, two ion conductor layers) of the multilayered structure may be formed of different materials or the same material. In some cases, one or more of the layers of the multilayered structure may include a lithium oxysulfide material, which is described in more detail below. Other configurations are also possible.

It should be understood that wherever lithium is described as an electroactive material, other suitable electroactive materials (including others described elsewhere herein) may be substituted. Also, wherever ceramics are described as ion conductors, other ion conductor materials (including others described elsewhere herein) may be used.

As described herein, a separator layer may be used as a polymer matrix upon which an ion conductor layer is deposited. According to one exemplary manufacturing process, a porous separator layer 500 as illustrated in FIG. 2 is provided. The porous separator layer may be conductive to ions or non-conductive. One example of a suitable film is a commercially available porous separator layer, such as those used in battery separators. The hole path through the layer may in some embodiments be highly tortuous. In certain embodiments, the hole path through the layer may completely penetrate the layer. This free-standing layer may then be coated with an ionic conductor (eg, ceramic, such as lithium oxysulfide).

The method of coating the free-standing separator with an ionic conductor material offers many advantages over other methods of making protective structures. The first of these is the fact that the resulting structure does not have to be released from the carrier substrate. This not only provides cost savings and material reduction, but also avoids the possibility of damage to the fragile ionic conductor coating during the release step. Second, bonding the ionic conductor material to the separator surface creates a mechanically stable platform for the thin ionic conductor (eg, ceramic) coating to resist the mechanical stress encountered when placed in a cell that is pressed against a rough cathode. Greatly enhances the ability of the coating to resist. Third, this process can be accomplished in a single chamber pump down. Eliminating the need to open the vacuum chamber during the deposition process minimizes material handling as well as reduces the chance of contamination.

As described herein, in some embodiments the ion conductor material may be deposited on the separator layer using a vacuum deposition process (eg, sputtering, CVD, thermal or E-beam evaporation). Vacuum deposition can allow for the deposition of a smooth, dense and homogeneous thin layer. In some embodiments, it is desirable to deposit a thin layer of inorganic ionic conductor material, since a thick layer can increase the internal resistance of the battery and lower the battery rate capability and energy density.

As illustratively shown in structure 504 of FIG. 3 , the voids of separator layer 500 (eg, separator) are substantially unfilled with ionic conductor 505 (eg, ceramic). In embodiments in which all or part of the separator layer pores are unfilled with an inorganic ionic conductor (eg, ceramic), these portions may be filled with an electrolyte solvent when placed in an electrochemical cell. In some embodiments, the ionic conductor may be coated with a final layer of electroactive material 510 (eg, lithium). The electroactive material layer may be configured to adhere to the ionically conductive layer, as described in more detail below. In certain embodiments of this process, no etching is involved, which can make the process very fast and efficient.

Also, although some figures shown herein illustrate a single ion conductor layer, in some embodiments the protective structure comprises multiple ion conductor layers (eg, at least 2, 3, 4, 5, or 6 ion conductor layers). It should be understood that this forms a multi-layered structure. As one example, an ion conductor layer (eg, an inorganic layer ion conductor layer) may be part of a multilayered structure comprising more than one ion conductor layer, wherein two or more layers (eg, two ions) of the multilayered structure conductor layers) are formed of different materials. In another example, two or more layers (eg, two ion conductor layers) of the multilayered structure are formed of the same material. In some cases, one or more of the multilayered structure layers may include a lithium oxysulfide material. The multilayered structure may optionally include polymer layers (eg, at least 1, 2, 3, 4, 5, or 6 polymer layers). In some embodiments, the polymer layer is positioned between two or more ion conductor layers. Each layer of the multilayered structure independently has characteristics (eg, thickness, conductivity, bulk electronic resistivity) generally described herein for the ion conductor layer and/or the polymer layer.

In structures comprising a single ion conductor layer, the ionic conductor layer (which in some embodiments may comprise lithium oxysulfide) may be in direct contact with the respective electroactive material of the first electrode and separator layer.

As described herein, in some embodiments directed to the formation of a protective structure by disposing an ionic conductor on the surface of a separator layer, it is desirable to increase the bond or adhesive strength between the ion conductor and the separator layer. As a result of the increased adhesion between the layers, the likelihood of delamination of the layers can be reduced, and the mechanical stability of the ion conductor layer can be improved during cycling of the cell. For example, the resulting ion conductor layer-separator composite may enhance the ability of the ion conductor layer to resist the mechanical stress encountered when placed in a cell that is pressed against a rough cathode. Thus, in some embodiments, prior to deposition of the ion conductor layer, the surface of the separator layer may be treated (eg, a pretreatment process) to increase the surface energy of the separator layer. The increased surface energy of the separator layer may allow for improved adhesion between the ion conductor layer and the separator as compared to when the separator surface was not treated.

In certain embodiments, adhesion is enhanced when the ratio of the thickness of the ion conductor layer to the average pore diameter of the separator is within a specific range described below.

To increase the surface energy of the separator layer (ie, to activate the surface of the separator layer), various methods can be used. The method may include, for example, a pretreatment step of treating the surface of the separator prior to deposition of the ion conductor material. In certain embodiments, the step of activating or pre-treating comprises treating the separator with a source of plasma. For example, an anode layer ion source (ALS) may be used to generate the plasma. In general, the anode layer ion source involves generating electrons by an applied potential in the presence of a working gas (working gas). The generated plasma generates additional ions and electrons, which are accelerated towards the target substrate (eg, separator layer), providing ion bombardment of the substrate. This bombardment of the separator layer substrate is followed by increasing the surface energy of the separator layer, which in turn improves the adhesion between the separator and the ion conductor material.

A variety of working gases may be used during a surface activation process, such as plasma treatment. In general, the surface activation is air, oxygen, ozone, carbon dioxide, carbonyl sulfide, sulfur dioxide, nitrous oxide, nitric oxide, nitrogen dioxide, nitrogen, ammonia, hydrogen, freon (eg, CF ₄ , CF ₂ Cl ₂ , CF ₃ Cl ), silane (eg, SiH ₄ , SiH ₂ (CH ₃ ) ₂ , SiH ₃ CH ₃ ), and/or argon.

In general, plasma treatment modifies the surface of the separator by ionizing the working gas and/or the surface and, in some instances, forming or depositing activated chemical functional groups on the surface. In certain embodiments, activation of certain functional groups on the surface of the separator layer can improve the bonding between the separator layer and the ionic conductor material. In certain embodiments, an activated functional group may include one or more of the following: carboxylate (eg, -COOH), thiol (eg, -SH), alcohol (eg, -OH), acyl (eg, -CO) ), sulfonic and/or sulfonic acids (such as -SOOH or -SO ₃ H), amines (such as -NH ₂ ), nitric oxide (such as -NO), nitrogen dioxide (such as -NO ₂ ), chlorides ( eg, —Cl), a haloalkyl group (eg, CF ₃ ), a silane (eg, SiH ₃ ), and/or an organosilane (SiH ₂ CH ₃ ). Other functional groups are also possible.

In certain embodiments, the plasma treatment, such as an ALS process, is performed in a chamber at a pressure in the range of ^{, for example, 10 -2} to 10 ^{-8 Torr.} For example, the pressure may be 10 ^-8 Torr or more, 10 ^-7 Torr or more, 10 ^-6 Torr or more, 10 ^-5 Torr or more, 10 ^-4 Torr or more, or 10 ^-3 Torr or more. The pressure may be 10 ^-2 Torr or less, 10 ^-3 Torr or less, 10 ^-4 Torr or less, 10 ^-5 Torr or less, or 10 ^-6 Torr or less. Combinations of the aforementioned ranges are also possible.

Plasma treatment can generally be performed with an ion source power in the range of, for example, 5W to 200W. For example, the output may be 5 W or more, 10 W or more, 20 W or more, 50 W or more, 100 W or more, or 200 W or more. The output may be 200 W or less, 100 W or less, 50 W or less, 20 W or less, or 5 W or less. Combinations of the power ranges described above are also possible.

The actual surface energy increase is a function of pressure, power and exposure time, without taking into account overexposure of the material, which can result in thermal damage. For example, the exposure time (i.e., the time the separator layer is plasma treated) may be 1 second or more, 10 seconds or more, 30 seconds or more, 1 minute or more, 2 minutes or more, 5 minutes or more, 10 minutes or more, 20 minutes or more, It may be at least 30 minutes, at least 1 hour, or at least 5 hours. The exposure time may be 10 hours or less, 1 hour or less, 30 minutes or less, 10 minutes or less, 5 minutes or less, 1 minute or less, 10 seconds or less, or 1 second or less. Combinations of the exposure times described above are also possible.

It will be understood by those skilled in the art that the setup conditions may vary depending on the efficiency of the plasma system, the efficiency of the power source, RF matching issues, gas distribution and selection, distance from the target substrate, plasma exposure time, and the like. Thus, various combinations of the power at which the plasma source is operated, the operating pressure, the gas selection, and the length of exposure time to the plasma source are possible.

Although plasma treatment has been primarily described for increasing the surface energy of a substrate (eg, a separator), other methods of increasing the surface energy of a substrate are also possible. For example, in certain embodiments, flame surface treatment, corona treatment, chemical treatment, surface oxidation, absorption of functional groups to the surface, and/or surface grafting may be used to increase the surface energy of the substrate.

The surface energy of the separator layer may be increased to any suitable value. In some embodiments, the surface energy of the separator layer prior to treatment may be, for example, 0-50 dyne. For example, the surface energy may be 0 dyne or more, 10 dyne or more, 20 dyne or more, 30 dyne or more, 40 dyne or more, or 50 dyne or more. The surface energy may be less than 50 dynes, less than 40 dynes, less than 30 dynes, less than 20 dynes, or less than 10 dynes. Combinations of the ranges described above are also possible. Other surface energies are also possible.

In some embodiments, the surface energy of the separator layer after treatment is, for example, between 30 dyne and 100 dyne (1 dyne = 1 g cm/s ² = 10 ^-5 kg m/s ² = 10 ^-5 N). can be a range. In certain embodiments, the surface energy of the separator layer after treatment may be at least 30 dyne, at least 40 dyne, at least 50 dyne, at least 60 dyne, at least 70 dyne, at least 80 dyne, or at least 90 dyne. The surface energy after treatment may be, for example, less than 100 dyne, less than 90 dyne, less than 80 dyne, less than 70 dyne, less than 60 dyne, or less than 50 dyne. Combinations of the ranges described above are also possible.

In certain embodiments, the surface energy of the separator surface before treatment is 1.2 times or more, 1.5 times or more, 2 times or more, 3 times or more, 5 times or more, 10 times or more, 20 times or more, 50 times or more, 70 times or more, after treatment. , or 100 times or more. In some cases, the surface treatment can be increased by a factor of 500 after treatment. Other increases in surface energy are also possible.

As described herein, in some embodiments the treatment of the surface creates a chemical and/or physical bond between the ionic conductor and the separator layer being formed. In some embodiments, the bond may comprise a covalent bond. Additionally or alternatively, non-covalent interactions (eg, hydrophobic and/or hydrophilic interactions, electrostatic interactions, van der Waals interactions) may be formed. In general, a treatment (eg, pretreatment) of a surface that produces bond formation increases the degree of adhesion between the two layers as compared to without such treatment.

To determine the relative adhesive strength between the two layers, a tape test may be performed. Briefly, the tape test uses a pressure sensitive tape to quantitatively estimate the adhesion between a first layer (eg, a separator layer) and a second layer (eg, an ionically conductive layer). In this test, an X-cut may be performed with a second layer (eg, an ionically conductive layer) through a first layer (eg, a separator layer). A pressure sensitive tape may be applied and removed over the fracture area. When the separator layer is maintained on the ion conductive layer (or vice versa), the adhesion is good. If the separator layer comes off together with the tape strip, the adhesion is poor. When held on the ion conductive layer, the adhesion is good. Tape testing may be performed according to standard ASTM D3359-02. In some embodiments, the adhesive strength between the separator and the inorganic ion conductor layer passes the tape test according to standard ASTM D3359-02, meaning that the ionic conductor layer does not peel from the separator layer during the test. In some embodiments, the tape test is performed when two layers (e.g., from a first layer, such as a separator layer to a second layer, such as an ionically conductive layer) are at least 5 times, at least 10 times, at least 15 times, at least 20 times, 50 times. After being incorporated into a cell that has been cycled at least 100 times, or at least 100 times, such as a lithium-sulfur cell or any other suitable cell described herein, the two layers pass the tape test after being removed from the cell (such as , the first layer does not delaminate from the second layer during the test).

A peel test may include measuring the adhesion or force required to remove a first layer (eg, a separator layer) from the length of a second layer (eg, an ionically conductive layer), which may include a tensile testing apparatus or It may be measured in N/m using another suitable instrument. Such experiments may optionally be performed in the presence of a solvent (eg, electrolyte) or other component to determine the effect of the solvent and/or component on adhesion.

In some embodiments, the adhesive strength between two layers (e.g., a first layer, such as a separator layer and a second layer, such as an ion conductor layer) can be increased as a result of a treatment (e.g., pretreatment) step described herein. . The adhesive strength after treatment may be, for example, in the range of 100 N/m to 2000 N/m. In certain embodiments, the adhesive strength is at least 50 N/m, at least 100 N/m, at least 200 N/m, at least 350 N/m, at least 500 N/m, at least 700 N/m, at least 900 N/m, It may be 1000 N/m or more, 1200 N/m or more, 1400 N/m or more, 1600 N/m or more, or 1800 N/m or more. In certain embodiments, the adhesive strength is 2000 N/m or less, 1500 N/m or less, 1000 N/m or less, 900 N/m or less, 700 N/m or less, 500 N/m or less, 350 N/m or less, 200 N/m or less, 100 N/m or less, or 50 N/m or less. Other adhesive strengths are also possible.

As described herein, the thickness of the ion conductor layer relative to the average pore diameter of the separator layer can affect the adhesive strength or degree of bonding between two layers in a composite. For example, in some cases the thickness of the ion conductor layer may be greater than the average pore diameter (or maximum pore diameter) of the separator layer, which prevents the formation of a smooth, dense, homogeneous ion conductor layer that resists delamination from the separator layer. to provide.

As described herein, in an electrochemical cell, the ionic conductor layer can act as a solvent barrier that acts to prevent or reduce the likelihood of interaction of the liquid electrolyte with an electroactive material (eg, lithium metal). In some embodiments, the ability of a composite ion conductor layer-separator to act as a barrier can be measured in part by an air permeation test (eg, Gurley test). The Gurley test determines the time required for a specific volume of air to flow through a standard area of a material. As such, larger air permeation times (Gurley-seconds) generally correspond to better barrier properties.

One of ordinary skill in the art would expect improved barrier properties (eg, higher air permeation times) to be achieved by the use of a relatively thick inorganic ion conductor layer, since thicker layers may be more difficult for fluid to penetrate through the layers. have. However, as described in more detail below, the present inventors have found that the reduced thickness of the ion conductor layer of the inorganic ion conductor layer-separator composite is lower than that of the inorganic ion conductor layer-separator composite having a relatively thick inorganic ion conductor layer. , observed that it provided an improvement in barrier properties, as measured by increasing the air permeation time using the Gurley test (see FIGS. 3 and 5 ). In addition, the combination of a thin inorganic ion conductor layer and a plasma treated separator results in a maximum air permeation time (and thus enhanced barrier properties) compared to composites not including the plasma treated separator or composites having a relatively thick inorganic ion conductor layer. ) was shown. Without wishing to be bound by any theory, the present inventors believe that the high transmission time and good barrier properties are partially due to the good adhesive strength between the two layers and the good mechanical flexibility (i.e. lower film stress) of the ion conductor layer. It is thought that it can contribute to reducing the cracking potential of the layer. Similar to delamination, cracking of the ion conductor layer typically results in poor barrier properties.

In some embodiments, the air permeation time of a composite described herein (eg, an ionic conductor layer-separator composite) is at least 1,000 Gurley-seconds, at least 5,000 Gurley-seconds, at least 10,000 Gurley-seconds, at least 20,000 Gurley-seconds, at least 40,000 Gurley-seconds. More than 60,000 gully-seconds or more, 80,000 gully-seconds or more, 100,000 gully-seconds or more, 120,000 gully-seconds or more, 140,000 gully-seconds or more, 160,000 gully-seconds or more, 180,000 gully-seconds or more, 200,000 gully-seconds or more , 500,000 Gurley-seconds or greater, or 10 ⁶ Gurley-seconds or greater. In some embodiments, the composite is substantially impermeable. In some embodiments, the air permeation time is ^{less than 10 6} Gurley-seconds, less than 500,000 Gurley-seconds, less than 200,000 Gurley-seconds, less than 150,000 Gurley-seconds, less than 120,000 Gurley-seconds, less than 80,000 Gurley-seconds, 40,000 Gurley-seconds. less than 20,000 Gurley-seconds, less than 10,000 Gurley-seconds, or less than 5,000 Gurley-seconds. The air permeation time and Gurley tests described herein refer to methods performed according to TAPPI standard T 536 om-12, which include a differential pressure of 3 kPa and a sample size of 1 square inch.

The ion conductors or ion conductor layers described herein may be formed of various types of materials. In certain embodiments, the material from which the ionic conductor is formed can be selected such that ions (eg, electrochemically active ions, such as lithium ions) penetrate the ionic conductor but substantially inhibit electrons from passing through the ionic conductor. By “substantially inhibiting” herein is meant that, in this embodiment, the material permits a flux of lithium ions that is at least ten times greater than the passage of electrons.

In some embodiments, the material used in the ionic conductor layer has a sufficiently high conductivity in the first amorphous state (eg, at least 10 ⁻⁶ S/cm, or another conductivity value described herein). The materials may also be selected for their ability to form smooth, dense, homogeneous thin films, particularly on polymeric layers, such as separators. Lithium oxysulfide may in particular include these characteristics.

In certain embodiments, an ionic conductor may be constructed to be electrically non-conductive, which may inhibit the extent to which the ionic conductor will cause a short circuit in an electrochemical cell. In certain embodiments, all or a portion of all or a portion of the ionic conductor is ^{at least about 10 4} Ohm-meters, at least about 10 ⁵ Ohm-meters, at least about 10 ¹⁰ Ohm-meters, at least about 10 ¹⁵ Ohm-meters, or about It may be formed of a material having a bulk electronic resistivity of 10 ^{20 Ohm-meters or greater.} The bulk electronic resistivity may, in some embodiments, be about 10 ²⁰ Ohm-meters or less, or about 10 ¹⁵ Ohm-meters or less. Combinations of the ranges described above are also possible. Other bulk electronic resistivity values are possible.

In some embodiments, the average ionic conductivity (eg, lithium ion conductivity) of the ionic conductor material is at least about 10 ⁻⁷ S/cm, at least about 10 ⁻⁶ S/cm, at least about 10 ⁻⁵ S/cm, at least about 10 ^{− 4} S/cm or more, about 10 ^-3 S/cm or more, about 10 ^-2 S/cm or more, about 10 ^-1 S/cm or more, about 1 S/cm or more, or about 10 S/cm or more. The average ionic conductivity may be about 20 S/cm or less, about 10 S/cm or less, or 1 S/cm or less. Conductivity can be measured at room temperature (eg, 25° C.).

In some embodiments, the ionic conductor may be a solid. In some embodiments, the ionic conductor may comprise, or be formed substantially from, a non-polymeric material. For example, the ionic conductor may comprise or be formed substantially from an inorganic material.

Although a variety of materials can be used as the ionically conductive layer, in one set of embodiments, the ionically conductive layer is an inorganic ionically conductive layer. For example, the inorganic ion conductor layer may be ceramic, glass, or vitreous-ceramic. In some embodiments, the ionic conductor comprises an oxysulfide, such as lithium oxysulfide.

In certain embodiments in which the inorganic ionic conductor material described herein comprises lithium oxysulfide, the lithium oxysulfide (or ionic conductor layer comprising lithium oxysulfide) may have an oxide content of 0.1 to 20 weight percent. The oxide content can be measured relative to the total weight of the lithium oxysulfide material or the total weight of the ion conductor layer comprising the lithium oxysulfide material. For example, the oxide content may be at least 0.1 wt%, at least 1 wt%, at least 2 wt%, at least 5 wt%, at least 10 wt%, at least 15 wt%, or at least 20 wt%. In some embodiments, the oxide content may be 20 wt% or less, 15 wt% or less, 10 wt% or less, 5 wt% or less, 2 wt% or less, or 1 wt% or less lithium oxysulfide. Combinations of the ranges described above are also possible. The elemental composition of the layer, including oxide content, can be determined by methods such as energy-dispersive X-ray spectroscopy.

In some embodiments wherein the inorganic ion conductor material described herein comprises lithium oxysulfide, the lithium oxysulfide material (or ionic conductor layer comprising lithium oxysulfide) comprises, for example, 1:1 to 1000:1 sulfur atoms. It has an atomic ratio of atoms to oxygen (S:O). For example, the atomic ratio of sulfur atoms to oxygen atoms (S:O) of a lithium oxysulfide material (or an ionic conductor layer comprising lithium oxysulfide) is 0.5:1 or more, 0.667:1 or more, 1:1 or more, 2: 1 or more, 3:1 or more, 4:1 or more, 5:1 or more, 10:1 or more, 20:1 or more, 50:1 or more, 70:1 or more, 90:1 or more, 100:1 or more, 200: 1 or more, 500:1 or more, or 1000:1 or more. The atomic ratio (S:O) of sulfur atoms to oxygen atoms in the lithium oxysulfide material (or ion conductor layer comprising lithium oxysulfide) is 1000:1 or less, 500:1 or less, 200:1 or less, 100:1 or less. , 90:1 or less, 70:1 or less, 50:1 or less, 20:1 or less, 10:1 or less, 5:1 or less, 3:1 or less, or 2:1 or less. Combinations of the ranges described above are also possible (eg, S:O atomic ratios of 2:1 to 1000:1, or 4:1 to 100:1). Other ranges are also possible. The elemental composition of the layer can be determined by methods such as energy-dispersive X-ray spectroscopy.

It should be noted that the above atomic ratio may also be expressed as the ratio of oxygen atoms to sulfur atoms (O:S), and the inverse of the above ratio may be applicable. For example, in some embodiments, a lithium oxysulfide material (or an ionic conductor layer comprising lithium oxysulfide) has an oxygen atom to sulfur atom ( lithium oxysulfide with an atomic ratio of O:S).

In some embodiments, the lithium oxysulfide materials described herein may have the formula x(yLi ₂ S+zLi ₂ O)+MS ₂ , wherein M is Si, Ge, or Sn, wherein y+z =1, and x may be 0.5 to 3. In certain embodiments, x is at least 0.5, at least 1.0, at least 1.5, at least 2.0, or at least 2.5. In other embodiments, x is 3.0 or less, 2.5 or less, 2.0 or less, 1.5 or less, 1.0 or less, or 0.5 or less. Combinations of the ranges described above are also possible. Other values for x are also possible.

The ionic conductor, in some embodiments, is an amorphous lithium-ion conductive oxysulfide, a crystalline lithium-ion conductive oxysulfide, or a mixture of an amorphous lithium-ion conductive oxysulfide and a crystalline lithium-ion conductive oxysulfide, such as an amorphous lithium oxysulfide. , crystalline lithium oxysulfide, or a mixture of amorphous lithium oxysulfide and crystalline lithium oxysulfide.

In some embodiments, the inorganic ion conductor, such as the lithium oxysulfide described above, comprises 0% to 30% by weight of the glass forming additive of the inorganic ion conductor material. Examples of glass forming additives include, for example, SiO ₂ , Li ₂ SiO ₃ , Li ₄ SiO ₄ , Li ₃ PO ₄ , LiPO ₃ , Li ₃ PS ₄ , LiPS ₃ , B ₂ O ₃ , B ₂ S ₃ . include Other glass forming additives are also possible. In certain embodiments, the glass forming additive may be at least 5 wt%, at least 10 wt%, at least 15 wt%, at least 20 wt%, at least 25 wt%, or at least 30 wt% of the inorganic ion conductor material. In certain embodiments, the glass forming additive may be up to 30 wt%, up to 25 wt%, up to 20 wt%, up to 15 wt%, or up to 10 wt% of the inorganic ion conductor material. Combinations of the ranges described above are also possible. Other values of glass forming additives are also possible.

In some embodiments, one or more addition salts (eg, lithium salts such as LiI, LiBr, LiCl, Li ₂ CO ₃ , or Li ₂ SO ₄ ) are added to the inorganic ion conductor material, eg, in the range of 0-50 mole %. can be Other salts are also possible. In certain embodiments, the addition salt is at least 0 mole%, at least 10 mole%, at least 20 mole%, at least 30 mole%, at least 40 mole%, or at least 50 mole%. In certain embodiments, the addition salt is 50 mole % or less, 40 mole % or less, 30 mole % or less, 20 mole % or less, or 10 mole % or less. Combinations of the ranges described above are also possible. Other mole % values are also possible.

Further examples of ionic conductors include lithium nitride, lithium silicate, lithium borate, lithium aluminate, lithium phosphate, lithium phosphorus oxynitride, lithium silicosulfide, lithium germanosulfide, lithium oxide (e.g., Li ₂ O, LiO, LiO ₂ , LiRO ₂ , where R is a rare earth metal), lithium lanthanum oxide, lithium titanium oxide, lithium borosulfide, lithium aluminosulfide, and lithium phosphosulfide, and combinations thereof.

In certain embodiments, the ion conductor is formed of a single-ion conductive material (eg, a single-ion conductive ceramic material).

Those skilled in the art will be able to select suitable materials for use as ionic conductors herein. Relative factors that may be taken into account when making this selection are the ionic conductivity of the ionic conductor material; the ability to deposit or form an ionic conductor material on or with another material in an electrochemical cell; brittleness of ionic conductor materials; compatibility of the ionic conductor material with the polymer or separator material; compatibility of ionic conductor materials with electrolytes in electrochemical cells; the ionic conductivity of the material (eg, lithium ion conductivity); and/or the ability to attach an ionic conductor to the separator material.

The ion conductor material may be subjected to any suitable method, such as sputtering, electron beam evaporation, vacuum thermal evaporation, laser ablation, chemical vapor deposition (CVD), thermal evaporation, plasma enhanced chemical vacuum deposition (PECVD), laser enhanced chemical vapor deposition, and jet deposition. can be settled by The technique used may depend on the type of material being deposited, the layer thickness, and the like.

As described herein, in certain preferred embodiments, the ion conductor material may be deposited on the separator using a vacuum deposition process (eg, sputtering, CVD, thermal or E-beam evaporation). Vacuum deposition allows the deposition of smooth, dense and homogeneous thin layers.

In embodiments where the ionic conductor is in the form of a layer (eg, a layer adjacent to and/or attached to a polymer layer (eg, separator)), the thickness of the ion conductor layer may vary. The thickness of the ion conductor layer can vary, for example, over the range of 1 nm to 7 microns. For example, the thickness of the ion conductor layer may be 1 to 10 nm, 10 to 100 nm, 10 to 50 nm, 30 to 70 nm, 100 to 1000 nm, or 1 to 7 microns. The thickness of the ion conductor layer may be, for example, 7 microns or less, 5 microns or less, 2 microns or less, 1000 nm or less, 600 nm or less, 500 nm or less, 250 nm or less, 100 nm or less, 70 nm or less, 50 nm or less. , 25 nm or less, or 10 nm or less. In some embodiments, the ion conductor layer is at least 10 nm thick, at least 20 nm thick, at least 30 nm thick, at least 100 nm thick, at least 400 nm thick, at least 1 micron thick, at least 2.5 microns thick, or at least 5 microns thick. . Other thicknesses are also possible. Combinations of the ranges described above are also possible.

As described herein, the methods and articles provided herein can allow for the formation of smooth surfaces. In some embodiments, the RMS surface roughness of the ion conductor layer of the protective structure can be, for example, less than 1 μm. In certain embodiments, the RMS surface roughness at such a surface is, for example, 0.5 nm to 1 μm (eg, 0.5 nm to 10 nm, 10 nm to 50 nm, 10 nm to 100 nm, 50 nm to 200 nm, 10 nm to 500 nm). In some embodiments, the RMS surface roughness is 0.9 μm or less, 0.8 μm or less, 0.7 μm or less, 0.6 μm or less, 0.5 μm or less, 0.4 μm or less, 0.3 μm or less, 0.2 μm or less, 0.1 μm or less, 75 nm or less, 50 nm or less, 25 nm or less, 10 nm or less, 5 nm or less, 2 nm or less, or 1 nm or less. In some embodiments, the RMS surface roughness can be greater than 1 nm, greater than 5 nm, greater than 10 nm, greater than 50 nm, greater than 100 nm, greater than 200 nm, greater than 500 nm, or greater than 700 nm. Other values are also possible. Combinations of the ranges described above are also possible (eg RMS surface roughness of less than or equal to 0.5 μm and greater than 10 nm). The polymeric layer of the protective structure may have an RMS surface roughness of one or more of the ranges described above.

The separator may be configured to inhibit (eg, prevent) physical contact between the first electrode and the second electrode that could result in a short circuit of the electrochemical cell. The separator can be configured to be substantially electrically non-conductive, which can suppress the extent to which the separator causes a short circuit of the electrochemical cell. In certain embodiments, all or a portion of the separator is ^{at least about 10 4} Ohm-meter, at least about 10 ⁵ Ohm-meter, at least about 10 ¹⁰ Ohm-meter, at least about 10 ¹⁵ Ohm-meter, or at least about 10 ²⁰ Ohm-meter ideal It may be formed of a material having a bulk electronic resistivity. Bulk electronic resistivity can be measured at room temperature (eg, 25° C.).

In some embodiments, the separator may be ionically conductive, while in other embodiments, the separator is substantially ionically non-conductive. In some embodiments, the average ionic conductivity of the separator is about 10 ^-7 S/cm or more, about 10 ^-6 S/cm or more, about 10 ^-5 S/cm or more, about 10 ^-4 S/cm or more, about 10 ^{− 2} S/cm or more, or about 10 ^-1 S/cm or more. In certain embodiments, the average ionic conductivity of the separator is about 1 S/cm or less, about 10 ^-1 S/cm or less, about 10 ^-2 S/cm or less, about 10 ^-3 S/cm or less, about 10 ^-4 S /cm or less, about 10 ^-5 S/cm or less, about 10 ^-6 S/cm or less, about 10 ^-7 S/cm or less, or about 10 ^-8 S/cm or less. Combinations of the ranges described above are also possible (eg, an average ionic conductivity of at ^{least about 10 −8} S/cm and ^{less than or equal to about 10 −1 S/cm).}

In some embodiments, the separator may be a solid. The separator may be porous to allow the electrolyte solvent to penetrate it. In some cases, the separator is substantially free of solvents (eg, in the form of a gel) other than solvents that may penetrate or be present in the pores of the separator. In other embodiments, the separator may be in the form of a gel.

In certain embodiments, the separator is a polymeric binder, which may include one or more polymeric materials described herein (eg, polymers described below for separators), and a filler comprising a ceramic or vitreous/ceramic material, such as an ionic conductor layer. mixtures of the substances described herein for

The separators described herein can be made of a variety of materials. The separator may be polymeric in some instances, or may be in the form of an inorganic material (eg, glass fiber filter paper) in other instances. Examples of suitable separator materials include polyolefins (such as polyethylene, poly(butene-1), poly(n-pentene-2), polypropylene, polytetrafluoroethylene), polyamines (such as poly(ethylene imine) and poly propylene imine (PPI)); polyamides (such as polyamide (nylon), poly(ε-caprolactam) (nylon 6), poly(hexamethylene adipamide) (nylon 66)), polyimides (such as polyimide, polynitrile, and poly (pyromellitimide-1,4-diphenyl ether) (Kapton (registered trademark)) (Nomex (registered trademark)) (Kevlar (registered trademark))); polyether ether ketone (PEEK); Vinyl polymers (such as polyacrylamide, poly(2-vinyl pyridine), poly(N-vinylpyrrolidone), poly(methylcyanoacrylate), poly(ethylcyanoacrylate), poly(butylcyano) acrylate), poly(isobutylcyanoacrylate), poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinyl fluoride), poly(2-vinyl pyridine), vinyl polymer, polychlorotrifluoroethylene, and poly(isohexylcyanoacrylate)); polyacetal; polyesters (eg, polycarbonate, polybutylene terephthalate, polyhydroxybutyrate); polyethers (poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), poly(tetramethylene oxide) (PTMO)); vinylidene polymers (eg, polyisobutylene, poly(methyl styrene), poly(methylmethacrylate) (PMMA), poly(vinylidene chloride), and poly(vinylidene fluoride)); polyaramids (such as poly(imino-1,3-phenylene iminoisophthaloyl) and poly(imino-1,4-phenylene iminoterephthaloyl)); polyheteroaromatic compounds (such as polybenzimidazole (PBI), polybenzobisoxazole (PBO) and polybenzobisthiazole (PBT)); polyheterocyclic compounds (eg, polypyrrole); Polyurethane; phenolic polymers (eg, phenol-formaldehyde); polyalkynes (eg, polyacetylene); polydiene (eg, 1,2-polybutadiene, cis or trans-1,4-polybutadiene); polysiloxanes such as poly(dimethylsiloxane) (PDMS), poly(diethylsiloxane) (PDES), polydiphenylsiloxane (PDPS), and polymethylphenylsiloxane (PMPS)); and inorganic polymers (eg, polyphosphazenes, polyphosphonates, polysilans, polysilazanes). In some embodiments, the polymer is poly(n-pentene-2), polypropylene, polytetrafluoroethylene, polyamide (such as polyamide (nylon), poly(ε-caprolactam) (nylon 6), poly( hexamethylene adipamide) (nylon 66)), polyimides (such as polynitrile, and poly(pyromellitimide-1,4-diphenyl ether) (Kapton®) (Nomex®) ) (Kevlar®)), polyether ether ketone (PEEK), and combinations thereof.

The mechanical and electrical properties (eg, conductivity, resistivity) of these polymers are known. Accordingly, one of ordinary skill in the art can select suitable materials based on the mechanical and/or electrical properties (eg, ionic and/or electrical conductivity/resistivity) of the polymers and/or those polymers, in conjunction with the description herein, to the knowledge of the art. based on which it can be modified to be ionically conductive (eg, conductive to a single ion). For example, if desired, the polymeric materials listed above can be prepared with salts such as lithium salts (eg, LiSCN, LiBr, LiI, LiClO ₄ , LiAsF ₆ , LiSO ₃ CF ₃ , LiSO _{3 ) to enhance ionic conductivity.} CH ₃ , LiBF ₄ , LiB(Ph) ₄ , LiPF ₆ , LiC(SO ₂ CF ₃ ) ₃ , and LiN(SO ₂ CF ₃ ) ₂ ) may be further included.

Additional examples of separators and separator materials suitable for use are described in U.S. Patent No. 6,153,337 (filed December 19, 1997, entitled "Separators for electrochemical cells") and U.S. Patent 6,306,545 (filed December 19, 1998) 17, titled "Separators for electrochemical cells"), including those comprising a layer of microporous zerogel, for example a layer of microporous pseudo-boehmite, either as a free-standing film or directly on one of the electrodes. It may be provided by application of a coating. Solid electrolytes and gel electrolytes may also function as polymer layers in addition to their electrolyte function. Examples of useful gel polymer electrolytes are polyethylene oxide, polypropylene oxide, polyacrylonitrile, polysiloxane, polyimide, polyphosphazene, polyether, sulfonated polyimide, perfluorinated membrane (Nafion resin), polydivinyl polyethylene glycol, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, derivatives thereof, copolymers thereof, crosslinked and network structures thereof, and blends thereof, and optionally, one or more plasticizers. These include, but are not limited to, those comprising one or more polymers selected from the group consisting of.

Other suitable materials that may be used to form all or part of the separator are disclosed in U.S. Patent Application Publication No. 2010/0327811, filed July 1, 2010, published by reference herein in its entirety for all purposes: December 30, 2010, title: "Electrode Protection in Both Aqueous and Non-Aqueous Electromechanical Cells, Including Rechargeable Lithium Batteries").

One skilled in the art herein will be able to select suitable materials for use as separators. Relevant factors that may be considered when making this selection include: the ionic conductivity of the separator material; the ability to deposit or form a separator material on or with another material in an electrochemical cell; the flexibility of the separator material; porosity (eg, overall porosity, average pore size, pore size distribution, and/or curvature) of the separator material; compatibility of the separator material with the manufacturing process used to fabricate the electrochemical cell; compatibility of separator materials with electrolytes in electrochemical cells; and/or the ability to adhere the separator material to the ion conductor material. In certain embodiments, the separator material may be selected based on its ability to survive the ion conductor deposition process without mechanical loss. For example, in embodiments in which relatively high temperatures or high pressures are used to form ionic conductor materials (eg, ceramic ion conductor materials), the separator material may be selected or configured to resist such high temperatures and pressures.

A person skilled in the art can use a simple screening test to select an appropriate separator material from a candidate material. One simple screening test involves placing the material as a separator in an electrochemical cell that requires the passage of ionic species across the material (e.g., through pores in the material) to function while maintaining electrical separation. . If the material in this test is substantially ionically conductive, an electric current will be generated upon discharge of the electrochemical cell. Another simple screening test involves the ability to increase the surface energy of a polymer by various methods described herein. The screening test may also include testing the adhesion between the separator described herein and the ion conductor layer. Another screening test may include testing the ability of the separator to not expand in the presence of electrolytes used in electrochemical cells. Other simple tests can be performed by those skilled in the art.

The thickness of the separator may vary. The thickness of the separator may vary, for example, over the range of 5 microns to 40 microns. For example, the thickness of the separator may be from 10 microns to 20 microns, from 20 microns to 30 microns, or from 20 microns to 40 microns. The thickness of the separator may be, for example, 40 microns or less, 30 microns or less, 25 microns or less, 10 microns or less, or 9 microns or less. In some embodiments, the separator is at least 9 microns thick, at least 10 microns thick, at least 20 microns thick, at least 25 microns thick, at least 30 microns thick, or at least 40 microns thick. Other thicknesses are also possible. Combinations of the ranges described above are also possible.

As described herein, the separator may have a smooth surface. In some embodiments, the RMS surface roughness of the separator can be, for example, less than 1 μm. In certain embodiments, the RMS surface roughness at such a surface is, for example, between 0.5 nm and 1 μm (eg, between 0.5 nm and 10 nm, between 10 nm and 50 nm, between 10 nm and 100 nm, between 50 nm and 200 nm; 10 nm to 500 nm). In some embodiments, the RMS surface roughness is 0.9 μm or less, 0.8 μm or less, 0.7 μm or less, 0.6 μm or less, 0.5 μm or less, 0.4 μm or less, 0.3 μm or less, 0.2 μm or less, 0.1 μm or less, 75 nm or less, 50 nm or less, 25 nm or less, 10 nm or less, 5 nm or less, 2 nm or less, or 1 nm or less. In some embodiments, the RMS surface roughness can be greater than 1 nm, greater than 5 nm, greater than 10 nm, greater than 50 nm, greater than 100 nm, greater than 200 nm, greater than 500 nm, or greater than 700 nm. Other values are also possible. Combinations of the ranges described above are also possible (eg RMS surface roughness of less than or equal to 0.5 μm and greater than 10 nm).

As described herein, the separator may be porous. In some embodiments, the polymer pore size can be, for example, less than 5 microns. In certain embodiments, the polymer pore size may be between 50 nm and 5 microns, between 50 nm and 500 nm, between 100 nm and 300 nm, between 300 nm and 1 micron, or between 500 nm and 5 microns. In some embodiments, the pore size may be 5 microns or less, 1 micron or less, 500 nm or less, 300 nm or less, 100 nm or less, or 50 nm or less. In some embodiments, the pore size may be greater than 50 nm, greater than 100 nm, greater than 300 nm, greater than 500 nm, or greater than 1 micron. Other values are also possible. Combinations of the ranges described above are also possible (eg pore sizes less than 300 nm and greater than 100 nm).

As described herein, the thickness of the ion conductor layer relative to the average pore diameter of the separator positioned adjacent to the ion conductor layer can affect the degree of adhesion strength of the two layers. For example, the thickness of the ion conductor layer may be greater than the average pore diameter (or maximum pore diameter) of the separator. In certain embodiments, the average thickness of the ion conductor layer is at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 1.7 times, at least 2 times, 2.5 times the average pore size (or maximum pore diameter) of the separator adjacent to the ion conductor layer. 2x or more, 2.7 times or more, 2.8 times or more, 3.0 times or more, 3.2 times or more, 3.5 times or more, 3.8 times or more, 4.0 times or more, 5.0 times or more, 7.0 times or more, 10.0 times or more, or 20.0 times or more. In certain embodiments, the average thickness of the ion conductor layer is 20.0 times or less, 10.0 times or less, 7.0 times or less, 5.0 times or less, 4.0 times or less, 3.8 times or less, the average pore size (or maximum pore diameter) of the separator adjacent to the ion conductor layer. times less than or equal to 3.5 times, less than or equal to 3.2 times, less than or equal to 3.0 times, less than or equal to 2.8 times, less than or equal to 2.5 times, or less than or equal to 2 times. Other combinations of average pore diameter and ion conductor layer thickness are also possible.

The ratio of the thickness of the ion conductor layer to the average pore diameter of the separator is, for example, at least 1:1 (eg 1.1:1), at least 2:1, at least 3:2, at least 3:1, at least 4:1 , at least 5:1, or at least 10:1. The ratio of the thickness of the ion conductor layer to the average pore diameter of the separator may be 10:1 or less, 5:1 or less, 3:1 or less, 2:1 or less (eg, 1.1:1), or 1:1 or less. Other rains are also possible. Combinations of the ranges described above are also possible.

As described herein, a variety of methods can be used to form the ion conductor/separator composite. The thickness of the composite may vary over the range of, for example, 5 microns to 40 microns. For example, the thickness of the composite may be between 10 and 20 microns, between 20 and 30 microns, or between 20 and 40 microns. The thickness of the composite may be, for example, 40 microns or less, 30 microns or less, 25 microns or less, 10 microns or less, 9 microns or less, or 7 microns or less. In some embodiments, the composite is at least 5 microns thick, at least 7 microns thick, at least 9 microns thick, at least 10 microns thick, at least 20 microns thick, at least 25 microns thick, at least 30 microns thick, or at least 40 microns thick. Other thicknesses are also possible. Combinations of the ranges described above are also possible.

In some embodiments, the composite has an average ionic conductivity (eg, lithium ion conductivity) of about 10 ^-7 S/cm or greater, about 10 ^-6 S/cm or greater, about 10 ^-5 S/cm or greater, about 10 ^-4 S or greater. /cm or more, about 10 ^-2 S/cm or more, about 10 ^-1 S/cm or more, about 1 S/cm or more, or about 10 S/cm or more. Conductivity can be measured at room temperature (eg, 25° C.).

The composite structures described herein comprising an ion conductor layer and a separator can be packaged alone (optionally with suitable components such as handling substrates) together with an electroactive material to form a protected electrode or electrochemical cell It may be a self-supporting structure assembled with

In certain embodiments, an electrochemical cell comprises a first electrode comprising an electroactive material, a second electrode, and a composite positioned between the first electrode and the second electrode. The composite includes a separator comprising pores having an average pore size and an inorganic ion conductor layer bonded to the separator. The separator may ^{have a bulk electronic resistivity of 10 4} Ohm meters or greater (eg, 10 ¹⁰ Ohm meters or greater, or 10 ¹⁵ Ohm meters or greater, such as 10 ¹⁰ Ohm meters to 10 ¹⁵ Ohm meters or greater). The inorganic ion conductor layer has a ^{lithium-ion conductivity of 10 −6} S/cm or more) and includes lithium oxysulfide having an oxide content of 0.1 to 20% by weight.

The ion conductor layer comprising lithium oxysulfide may be a single layer in direct contact with the first electrode and the separator, respectively. In other cases, the ion conductor layer is part of a multilayered structure comprising more than one ion conductor layer. Optionally, two or more layers of the multilayered structure are formed of different materials. In other cases, two or more layers of the multilayered structure are formed of the same material.

Lithium oxysulfide may have the formula x(yLi ₂ S+zLi ₂ O)+MS ₂ , wherein M is Si, Ge, or Sn, wherein y+z=1 and x is 0.5 to 3 can be Optionally, the ion conductor layer comprises 0% to 30% by weight of the glass forming additive of the inorganic ion conductor material. The ion conductor layer may also optionally include one or more lithium salts, such as LiI, LiBr, LiCl, Li ₂ CO ₃ , and/or Li ₂ SO ₄ , although other salts described herein are also possible. One or more lithium salts may be added to the inorganic ion conductor material, for example, from 0 to 50 mole %.

The adhesive strength between the separator and the inorganic ion conductor layer may, in some cases, be strong enough to pass the tape test according to standard ASTM D3359-02. In some cases, the adhesive strength between the separator and the inorganic ion conductor layer may be at least 350 N/m or at least 500 N/m. In some examples, the inorganic ion conductor layer is covalently bonded to the separator. Covalent bonding may be accomplished by any suitable method described herein, one embodiment comprising the addition or plasma treatment of the inorganic ion conductor layer and the separator prior to or addition of the separator.

In some examples, the ratio of the thickness of the inorganic ion conductor layer to the average pore size of the separator is at least 1.1:1 (eg, at least 2:1, at least 3:1, or at least 5:1).

The inorganic ion conductor layer has a thickness of 2.0 microns or less (eg, 1.5 microns or less, 1.3 microns or less, 1 micron or less, 800 nm or less, 600 nm or less, or 400 nm to 600 nm).

In some examples, a separator having a thickness of 5 microns to 40 microns is included. The separator is a solid polymer separator. For example, the separator may be poly(n-pentene-2), polypropylene, polytetrafluoroethylene, polyamide (eg, polyamide (nylon), poly(ε-caprolactam) (nylon 6), poly(hexamethylene) adipamide) (nylon 66)), polyimides (such as polynitrile, and poly(pyromellitimide-1,4-diphenyl ether) (Kapton®) (Nomex®) ( Kevlar®)), polyether ether ketone (PEEK), and combinations thereof. The separator may also include or be formed from other polymers or materials described herein.

In certain embodiments, the separator may comprise a filler comprising a ceramic or glassy/ceramic material, such as a mixture of the material described herein for an ion conductor layer and a polymeric binder.

The separator may have an average pore size of 5 microns or less, 1 micron or less, 0.5 microns or less, 0.05 to 5 microns, or 0.1 to 0.3 microns.

The composite is, according to the Gurley test TAPPI standard T 536 om-12, at least 20,000 Gurley-seconds, at least 40,000 Gurley-seconds, at least 60,000 Gurley-seconds, at least 80,000 Gurley-seconds, at least 100,000 Gurley-seconds, or at least 120,000 Gurley-seconds. It may have a longer air permeation time. The composite may have an air permeation time of 300,000 Gurley-seconds or less, according to the air permeation time Gurley test TAPPI standard T 536 om-12.

The composite may be formed by, for example, depositing an ion conductor layer on the separator by a vacuum deposition process such as electron beam evaporation, or a sputtering process.

Although the composites described herein can be used in a variety of electrochemical cells, in one set of embodiments, the composites are comprised within a lithium cell, such as a lithium-sulfur cell. Thus, the first electrode may comprise lithium, such as lithium metal and/or a lithium alloy, as the first electroactive material, and the second electrode comprises sulfur as the second electroactive material.

In one set of embodiments, an electrochemical cell comprises: a first electrode comprising lithium, a second electrode comprising sulfur, a separator arranged between the first electrode and the second electrode, and in contact with and/or the separator A lithium-sulfur battery comprising a solid ion conductor bound thereto, wherein the solid ion conductor comprises a lithium-ion conducting oxysulfide.

For example, in embodiments in which a polymer layer is positioned on a substrate (eg, an ionic conductor layer) as part of a multi-layer protective structure, the polymer layer may be cured on or prepared directly on the substrate, or the polymer may be separately described. can be added to

The polymer layer may be solid (eg, as opposed to a gel). In certain embodiments, the polymeric layer can be configured to be electrically non-conductive, and is about 10 ⁴ Ohm-meter or greater, about 10 ⁵ Ohm-meter or greater, about 10 ¹⁰ Ohm-meter or greater, about 10 ¹⁵ Ohm-meter or greater, and about 10 15 Ohm-meter or greater. or greater, or from a material having a bulk electronic resistivity greater ^{than or equal to about 10 20 Ohm-meters.}

In some embodiments, the polymer may be ionically conductive. In some embodiments, the average ionic conductivity of the polymer is at least about 10 ^-7 S/cm, at least about 10 ^-6 S/cm, at least about 10 ^-5 S/cm, at least about 10 ^-4 S/cm, at least about 10 ^{− 2} S/cm or more, or about 10 ^-1 S/cm or more. In certain embodiments, the average ionic conductivity of the polymer is about 1 S/cm or less, about 10 ^-1 S/cm or less, about 10 ^-2 S/cm or less, about 10 ^-3 S/cm or less, about 10 ^-4 S /cm or less, about 10 ^-5 S/cm or less, about 10 ^-6 S/cm or less, about 10 ^-7 S/cm or less, or about 10 ^-8 S/cm or less. Combinations of the ranges described above are also possible (eg, an average ionic conductivity of at ^{least about 10 −8} S/cm and ^{less than or equal to about 10 −1 S/cm).} Conductivity can be measured at room temperature (eg, 25° C.).

The polymeric layers described herein can be made of a variety of materials. Examples of materials that may be suitable for use in the polymer layer include polyamines (eg, poly(ethylene imine) and polypropylene imine (PPI)); polyamides (such as polyamide (nylon), poly(ε-caprolactam) (nylon 6), poly(hexamethylene adipamide) (nylon 66)), polyimides (such as polyimide, polynitrile, and poly (pyromellitimide-1,4-diphenyl ether) (Kapton)); Vinyl polymers (such as polyacrylamide, poly(2-vinyl pyridine), poly(N-vinylpyrrolidone), poly(methylcyanoacrylate), poly(ethylcyanoacrylate), poly(butylcyano) acrylate), poly(isobutylcyanoacrylate), poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinyl fluoride), poly(2-vinyl pyridine), vinyl polymer, polychlorotrifluoroethylene, and poly(isohexylcyanoacrylate)); polyacetal; polyolefins (eg, poly(butene-1), poly(n-pentene-2), polypropylene, polytetrafluoroethylene); polyesters (eg, polycarbonate, polybutylene terephthalate, polyhydroxybutyrate); polyethers (poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), poly(tetramethylene oxide) (PTMO)); vinylidene polymers (eg, polyisobutylene, poly(methyl styrene), poly(methylmethacrylate) (PMMA), poly(vinylidene chloride), and poly(vinylidene fluoride)); polyaramids (such as poly(imino-1,3-phenylene iminoisophthaloyl) and poly(imino-1,4-phenylene iminoterephthaloyl)); polyheteroaromatic compounds (such as polybenzimidazole (PBI), polybenzobisoxazole (PBO) and polybenzobisthiazole (PBT)); polyheterocyclic compounds (eg, polypyrrole); Polyurethane; phenolic polymers (eg, phenol-formaldehyde); polyalkynes (eg, polyacetylene); polydiene (eg, 1,2-polybutadiene, cis or trans-1,4-polybutadiene); polysiloxanes such as poly(dimethylsiloxane) (PDMS), poly(diethylsiloxane) (PDES), polydiphenylsiloxane (PDPS), and polymethylphenylsiloxane (PMPS)); and inorganic polymers (eg, polyphosphazenes, polyphosphonates, polysilans, polysilazanes). In some embodiments, the polymer may be selected from the group consisting of polyvinyl alcohol, polyisobutylene, epoxy, polyethylene, polypropylene, polytetrafluoroethylene, and combinations thereof. The mechanical and electrical properties (eg, conductivity, resistivity) of these polymers are known. Accordingly, one skilled in the art can select suitable materials based on the mechanical and/or electrical properties (eg, ionic and/or electrical conductivity) of the polymers and/or can select these polymers based on their knowledge in the art in conjunction with the description herein. It can be modified to be ionically conductive (eg, conductive to a single ion). For example, if desired, the polymeric materials listed above can be prepared with salts such as lithium salts (eg, LiSCN, LiBr, LiI, LiClO ₄ , LiAsF ₆ , LiSO ₃ CF ₃ , LiSO _{3 ) to enhance ionic conductivity.} CH ₃ , LiBF ₄ , LiB(Ph) ₄ , LiPF ₆ , LiC(SO ₂ CF ₃ ) ₃ , and LiN(SO ₂ CF ₃ ) ₂ ) may be further included.

One skilled in the art herein will be able to select an appropriate material for use as the polymer layer. Relative factors that may be taken into account when making this selection are the ionic conductivity of the polymeric material; the ability to deposit or form a polymeric material on or with other materials in an electrochemical cell; the flexibility of the polymeric material; porosity (eg, overall porosity, pore size distribution, and/or curvature) of the polymeric material; compatibility of the polymeric material with the manufacturing process used to make the electrochemical cell; compatibility of polymeric materials with electrolytes in electrochemical cells; and/or the ability to attach the polymeric material to the ionic conductor material.

The thickness of the polymer layer may vary. The thickness of the polymer layer can be, for example, 40 microns or less, 30 microns or less, 25 microns or less, 10 microns or less, 5 microns or less, 3 microns or less, 2 microns or less, 1 micron or less, 0.5 microns or less, 0.1 microns or less, or 0.05 It can be sub-micron. In some embodiments, the polymer layer is at least 0.01 microns thick, at least 0.05 microns thick, at least 0.1 microns thick, at least 0.5 microns thick, at least 1 micron thick, at least 2 microns thick, at least 5 microns thick, at least 10 microns thick, 20 microns thick. greater than or equal to 25 microns thick, greater than or equal to 30 microns thick, or greater than or equal to 40 microns thick. Other thicknesses are also possible. Combinations of the ranges described above are also possible.

In some embodiments, an electrode, such as a first electrode (eg, electrode 102 in FIGS. 1A and 1B ), comprises an electroactive material comprising lithium. Suitable electroactive materials comprising lithium include, but are not limited to, lithium metal (such as lithium deposited on lithium foils and/or conductive substrates) and lithium metal alloys (such as lithium-aluminum alloys and lithium-tin alloys). not limited In some embodiments, the electroactive lithium-containing material of the electrode comprises greater than 50 weight percent lithium. In some cases, the electroactive lithium-containing material of the electrode comprises greater than 75 weight percent lithium. In another embodiment, the electroactive lithium-containing material of the electrode comprises greater than 90 weight percent lithium. Other examples of electroactive materials that may be used (eg, in the first electrode, which may be the negative electrode) are other alkali metals (eg, sodium, potassium, rubidium, cesium, francium), alkaline earth metals (eg, beryllium, magnesium). , calcium, strontium, barium, radium) and the like). In some embodiments, the first electrode is an electrode for a lithium ion electrochemical cell. In some cases, the first electrode is an anode or negative electrode.

The second electrode (eg, electrode 102 in FIGS. 1A and 1B ) may comprise a variety of suitable electroactive materials. In some cases, the second electrode is a cathode or a positive electrode.

In some embodiments, the electroactive material inside the electrode (eg, positive electrode) is a metal oxide, such as LiCoO ₂ , LiCo _x Ni _(1-x) O ₂ , LiCo _x Ni _y Mn _{(lxy) (} eg, LiNi _{1 / 3} Mn _{1 /3} Co _{1 /3} O ₂ ), LiMn ₂ O ₄ , and combinations thereof. In some embodiments, the electrode active material in the electrode (eg, positive electrode) may include lithium transition metal phosphate (eg, LiFePO ₄ ), which, in certain embodiments, may be substituted with borates and/or silicates. .

In certain embodiments, the electroactive material in the electrode (eg, positive electrode) can include an electroactive transition metal chalcogenide, an electroactive conductive polymer, and/or an electroactive sulfur-containing material, and combinations thereof. As used herein, the term “chalcogenide” refers to a compound containing one or more of the elements of oxygen, sulfur and selenium. Examples of suitable transition metal chalcogenides include, but are not limited to, Mn, V, Cr, Ti, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Hf, electroactive oxides, sulfides and selenides of transition metals selected from the group consisting of Ta, W, Re, Os, and Ir. In one embodiment, the transition metal chalcogenide is selected from the group consisting of electroactive oxides of nickel, manganese, cobalt, and vanadium, and electroactive sulfides of iron. In one embodiment, the electrode (eg, positive electrode) may comprise an electroactive conductive polymer. Examples of suitable electroactively conductive polymers include, but are not limited to, electroactive and electrically conductive polymers selected from the group consisting of polypyrrole, polyaniline, polyphenylene, polythiophene, and polyacetylene. In certain embodiments, it may be desirable to use polypyrrole, polyaniline, and/or polyacetylene as conductive polymers.

In certain embodiments, the electrode active material in the electrode (eg, positive electrode) may comprise sulfur. In some embodiments, the electroactive material in the electrode may comprise an electroactive sulfur-containing material. As used herein, "electroactive sulfur-containing material," means an electrode active material comprising any form of elemental sulfur, wherein the electrochemical activity includes the oxidation or reduction of a sulfur atom or moiety. As an example, the electroactive sulfur-containing material may include elemental sulfur (eg, S ₈ ). In some embodiments, the electroactive sulfur-containing material comprises a mixture of elemental sulfur and a sulfur-containing polymer. Accordingly, suitable electroactive sulfur-containing materials may include, but are not limited to, elemental sulfur, sulfides or polysulfides (eg, of alkali metals), which are organic or inorganic, and contain sulfur and carbon atoms. organic materials, which may or may not be polymeric. Suitable organic materials include, but are not limited to, those further comprising heteroatoms, conductive polymer segments, composites, and conductive polymers. In some embodiments, the electroactive sulfur-containing material in the electrode (eg, positive electrode) comprises at least about 40 weight percent sulfur. In some cases, the electroactive sulfur-containing material comprises at least about 50 wt%, at least about 75 wt%, or at least about 90 wt% sulfur.

Examples of sulfur-containing polymers are described in US Pat. Nos. 5,601,947 and 5,690,702 to Skotheim et al; US Pat. Nos. 5,529,860 and 6,117,590 to Scotime et al.; US Pat. No. 6,201,100 issued Mar. 13, 2001 to Gorkovenko et al., and PCT Publication No. WO 99/33130. Other suitable electroactive sulfur-containing materials comprising polysulfide linkages are described in US Pat. Nos. 5,441,831 to Scotime et al.; US Pat. Nos. 4,664,991 to Perichaud et al. and US Pat. Nos. 5,723,230, 5,783,330, 5,792,575 and 5,882,819 to Naoi et al. Additional examples of electroactive sulfur-containing materials are described, for example, in US Pat. Nos. 4,739,018 to Armand et al; US Pat. Nos. 4,833,048 and 4,917,974 to De Jonghe et al.; US Pat. Nos. 5,162,175 and 5,516,598 to Visco et al.; and those containing disulfide groups as described in U.S. Pat. No. 5,324,599 to Oyama et al.

Although sulfur is predominantly described as the electroactive species in the second electrode (which may for example be a porous positive electrode), wherever sulfur is described herein as a component of an electroactive material in an electrode, any suitable electroactive species may be used. For example, in certain embodiments, the electroactive species in the second electrode (eg, a porous positive electrode) may include hydrogen-absorbing alloys, such as those commonly used in nickel metal hybrid batteries. One skilled in the art herein will be able to extend the ideas described herein to electrochemical cells containing electrodes using other active materials.

The embodiments described herein may be used in connection with any type of electrochemical cell. In certain embodiments, the electrochemical cell is a primary (non-rechargeable) battery. In other embodiments, the electrochemical cell may be a secondary (rechargeable) battery. Certain embodiments relate to lithium rechargeable batteries. In certain embodiments, the electrochemical cell comprises a lithium-sulfur rechargeable battery. However, it will be understood that wherever lithium batteries are described, any similar alkali metal batteries may be used. Also, while embodiments of the present invention are particularly useful for the protection of lithium anodes, the embodiments described herein may be applicable to other applications where electrode protection is desired.

Any suitable electrolyte may be used in the electrochemical cells described herein. In general, the choice of electrolyte will depend on the chemistry of the electrochemical cell, and in particular the ionic species transported between the electrodes in the electrochemical cell. In some embodiments, suitable electrolytes may include one or more ionic electrolyte salts that provide ionic conductivity and one or more liquid electrolyte solvents, gel polymeric materials, or other polymeric materials. Examples of useful non-aqueous liquid electrolyte solvents include non-aqueous organic solvents such as N-methyl acetamide, acetonitrile, acetal, ketal, ester, carbonate, sulfone, sulfite, sulfolane, sulfoxide, aliphatic ether, cyclic Ethers, glymes, polyethers, phosphate esters, siloxanes, dioxolane (such as 1,3-dioxolane), N-alkylpyrrolidone, bis(trifluoromethanesulfonyl)imide, of the foregoing substituted forms, and blends thereof. Fluorinated derivatives of the foregoing are also useful as liquid electrolyte solvents. In some cases, an aqueous solvent may be used as the electrolyte for a lithium battery. The aqueous solvent may comprise water, which may contain other constituents, such as ionic salts. In some embodiments, the electrolyte may include a species such as lithium hydroxide, or other species that renders the electrolyte basic, to reduce the concentration of hydrogen ions in the electrolyte.

The electrolyte may include one or more ionic electrolyte salts to provide ionic conductivity. In some embodiments, one or more lithium salts (eg, LiSCN, LiBr, LiI, LiClO ₄ , LiAsF ₆ , LiSO ₃ CF ₃ , LiSO ₃ CH ₃ , LiBF ₄ , LiB(Ph) ₄ , LiPF ₆ , LiC(SO _{2 )} CF ₃ ) ₃ , and LiN(SO ₂ CF ₃ ) ₂ ) may be included. Other electrolyte salts that may be useful include lithium polysulfide (Li ₂ S _x ), and lithium salts of organic ionic polysulfide (LiS _x R) _n , where x is an integer from 1 to 20 and n is from 1 to 3 and R is an organic group), and those disclosed in U.S. Patent No. 5,538,812 to Lee et al. A concentration range of the ionic lithium salt in the solvent may be used, for example, from about 0.2 m to about 2.0 m, where m is mole/kg of solvent. In some embodiments, concentrations ranging from about 0.5 m to about 1.5 m are used. The addition of an ionic lithium salt to the solvent is advantageous in that the lithium sulfide or polysulfide formed upon discharging of the Li/S cell typically provides ionic conductivity to the electrolyte, which may render the addition of the ionic lithium salt unnecessary; It is arbitrary.

It should be understood that the electrochemical cells and components shown in the figures are exemplary, and the orientation of the components may vary. Also, non-planar arrangements, arrangements with fractions of materials different from those shown, and other alternative arrangements are useful in connection with certain embodiments of the present invention. Typical electrochemical electricity may also include, for example, storage structures, current collectors, external circuits, and the like. Those skilled in the art will be aware of many arrangements that can be used with the general and schematic arrangements shown in the drawings and described herein.

Where a layer is described herein as being “on,” “on,” or “adjacent to,” another layer, it may be directly on, on top of, or adjacent to, said layer; An intervening layer may also be present. A layer that is “directly on another layer”, “directly adjacent to another layer” or “in contact with another layer” has no interlayer present. Similarly, a layer located “between” two layers may exist directly between the two layers, or an interlayer may exist.

The following examples are intended to illustrate specific embodiments of the invention, but do not illustrate the full scope of the invention.

Example

Example 1A

This example describes a method of making an ion conductor layer on a freestanding separator (eg, an ion conductor-separator composite) with interlayer adhesive strength.

A commercial separator Celgard 2400 having a pore diameter of 100 nm to 200 nm was used as a substrate. The separator was pretreated with plasma using an anode layer ion source in a chamber at a pressure ^{of 10 −3} Torr, 50 W output in the presence of argon gas. Treatment was continued for 7 minutes. Before plasma treatment, the surface energy of the separator was 32 dyne. The separator surface energy after plasma treatment was greater than 70 dyne as measured with a dyne pen set .

Next, a layer of lithium oxysulfide, which is an ion conductor, was deposited on a separator by e-beam evaporation to form an ion conductor layer. The main components of the lithium oxysulfide layer were lithium, silicon, sulfur and oxygen (with ratios of Si:O = 1.5:1, S:O = 4.5:1, and S:Si = 3.1:1). In three experiments, the thickness of the ion conductor layer ranged from about 600 to 800 nm, as shown in Figs. 4a to 4c. The ratio of the thickness of the ion conductor layer to the pore diameter of the separator in these experiments ranged from about 3:1 to 8:1.

4A, 4B and 4C are scanning electron microscope (SEM) images showing an ion conductor (lithium oxysulfide) coating on a commercial separator. 4A is a SEM of a lithium oxysulfide coating on a 25-micron-thick separator. The thickness of the lithium oxysulfide layer was 610 nm. 4B is a SEM of a lithium oxysulfide layer on a 25 micron separator. The thickness of the lithium oxysulfide layer was 661 nm. 4C is an SEM cross-sectional image of an 800 nm thick lithium oxysulfide coating on a separator material. These images also show that the lithium oxysulfide material did not penetrate the pores of the separator.

The tape test was performed according to standard ASTM-D3359-02 to determine the adhesion between the ion conductor layer and the separator. This test demonstrated that the ion conductor was well bonded to the separator and did not peel off from the separator.

This example shows that pretreatment of the separator surface with plasma prior to deposition of the ion conductor (lithium oxysulfide) layer improves the adhesion of the ion conductor layer to the separator compared to the case without the pretreatment step (Comparative Example 1). show that it was done

Example 1B

An ion conductor-separator composite similar to that described in Example 1A was prepared, except that the lithium oxysulfide ion conductor layer had a thickness of 1 micron. The separator surface was treated with plasma as described in Example 1A prior to deposition of the lithium oxysulfide layer.

The final composite, as measured by the Gurley test performed at a differential pressure of 3 kPa (TAPPI standard T 536 om-12), was an untreated separator (i.e., a separator not treated with plasma prior to deposition of a lithium oxysulfide layer, Comparative Example) 1) showed a 17-fold reduced air permeation rate compared to 1). The final composite had an air permeation time of greater than 168 minutes compared to about 9.7 minutes in the composite including the untreated separator (Comparative Example 1).

This example shows that pretreatment of the separator surface with plasma prior to deposition of the ion conductor (lithium oxysulfide) layer increases the air permeation time of the composite compared to composites comprising an untreated separator (Comparative Example 1) give.

comparative example One

The following is a comparative example describing an ion conductor layer poorly bonded to a separator.

The method described in Example 1 was used for the preparation of the ion conductor-separator composite, except that the separator was not treated with plasma prior to deposition of the ion conductor layer.

The ion conductor-separator composite did not pass the tape test, demonstrating delamination of the ion conductor layer from the separator.

At a ceramic thickness of 1 micron, the air permeation time was less than 9.7 minutes as measured by the Gurley test (TAPPI standard T 536 om-12).

Example 2

This example demonstrates the preparation and performance of the ion conductor-separator composite of Example 1 in a lithium-sulfur electrochemical cell.

The ion conductor (lithium oxysulfide)-coated separator of Example 1 was vacuum coated with metallic lithium (about 25 microns of lithium deposited on top of a layer of lithium oxysulfide). The lithium anode was protected with a lithium oxysulfide-coated separator and assembled into a lithium-sulfur battery cell.

The cathode contained 55 wt% sulfur, 40 wt% carbon black and 5 wt% polyvinyl alcohol binder. The sulfur surface loading amount was about 2 mg/cm ² .

The active electrode covered a total surface area ^{of 16.57 cm 2 .} A lithium-sulfur battery cell was prepared with an electrolyte containing 16% by weight lithium bis(trifluoromethanesulfonyl)imide, 42% by weight dimethoxyethane, and 42% by weight 1,3-dioxolane solvent. was charged.

Lithium-sulfur battery The cell was discharged to 1.7 V at 3 mA and charged at 3 mA. Charging was terminated when the lithium-sulfur battery cell reached 2.5 V or when the charging time exceeded 15 hours when the cell could not reach 2.5 V.

The lithium-sulfur battery cell was cycled 30 times and showed the ability to reach 2.5 V in each cycle, demonstrating that the lithium oxysulfide layer functioned well as a barrier protecting lithium from polysulfide shuttles. did. Multiple cells overhauled after 10 charge cycles showed no defects in the lithium oxysulfide layer and no evidence of lithium metal deposition on top of the lithium oxysulfide layer. All lithium was deposited under the lithium oxysulfide layer. Overhaul also showed that the ceramic and separator materials were well bonded after cycling.

comparative example 2

This example shows the preparation and performance of the ion conductor-separator composite of Comparative Example 1 in a lithium-sulfur electrochemical cell.

An anode with lithium vacuum deposited on top of the ion conductor-separator composite of Comparative Example 1 was assembled into a lithium-sulfur battery cell and tested similarly as described in Example 2.

These cells could not be charged over 30 cycles to 2.5 V. Instead, the charging time was 15 hours or longer, and the charging voltage was leveled at 2.37 to 2.41 V. These results demonstrated that lithium was not protected from polysulfide shuttles during cycling. Overhaul showed that the lithium oxysulfide layer was defective and a significant portion of lithium (about 20-30% of the surface area) was deposited on top of this layer.

Example 3

This example demonstrates the ability of an ion conductor-separator composite (prepared similarly to the method described in Example 1) to act as a barrier to fluid, as demonstrated by the air permeation test (Gurley test). Each sample included a 25 micron thick separator with a pore diameter ranging from 0.1 microns to 0.5 microns, and a lithium oxysulfide coating on top of the separator. Samples 1, 2, 3, and 6 included separators that were plasma treated prior to lithium oxysulfide addition. Samples 4, 5, and 7 included untreated separators prior to addition of the lithium oxysulfide layer.

5 is a graph depicting air permeation time versus ion conductor layer thickness in composites comprising plasma treated and untreated separators. The figure shows that plasma treatment of the separator prior to application of the lithium oxysulfide coating (i.e., samples 1, 2, 3, and 6) show the improvement in air permeation time.

This example shows that plasma treatment of the separator surface prior to deposition of the oxysulfide layer generally increases the air permeation time, which promotes sufficient bonding between the oxysulfide layer and the separator. Absence of plasma treatment results in delamination of the oxysulfide layer and thus poorer barrier properties. This example also shows that the highest air permeation time (and thus enhanced barrier properties) was achieved with a lithium oxysulfide layer having a thickness of 0.5 microns (Sample 1). These data show that, in general, thinner lithium oxysulfide layers provide improved barrier properties compared to composites with thicker lithium oxysulfide layers, and that the combination of a thin lithium oxysulfide layer and plasma treated separator has the highest air permeation time ( Therefore, it suggests that it exhibits enhanced barrier properties).

Several embodiments of the present invention have been described and described herein, and various other means for those skilled in the art to perform the above function and/or obtain one or more of the results and/or advantages described herein and/or structures, each such variation and/or adaptation is considered to be within the scope of the present invention. More generally, those skilled in the art will appreciate that all parameters, dimensions, materials, and configurations described herein are to be construed as illustrative, and/or that the actual parameters, dimensions, materials, and/or configurations are not consistent with the teachings of the present invention. It will be readily appreciated that will depend on the specific application or applications being used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Accordingly, it is to be understood that the foregoing embodiments have been presented by way of example only, and that, within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, and/or method described herein. Additionally, any combination of two or more such features, systems, articles, materials, and/or methods is a feature of the invention unless such features, systems, articles, materials and/or methods are mutually inconsistent. included in the category.

As used herein in the specification and claims, the singular, unless expressly stated to the contrary, should be understood to mean "one or more."

As used herein in the specification and claims, the phrase “and/or” refers to “one or both” of elements connected to each other, i.e., elements that are co-existing in some cases and separate in other cases. should be understood to mean Unless expressly stated otherwise, elements other than those specifically identified by the phrase "and/or" may optionally be present with or not related to the specifically identified element. Thus, as a non-limiting example, in one embodiment, when used in conjunction with an open language such as "comprising," "A and/or B" means A without B (optionally including elements other than B). ), in other embodiments, without A (optionally including elements other than A), even in yet another embodiment, both A and B (optionally including other elements), etc. .

As used herein in the specification and claims, "or" should be understood to have the same meaning as "and/or" as previously defined. For example, "or" or "and/or" may be construed as inclusive when items in a list are separated. That is, it will be construed that it may include one or more of several or list elements, but may include more than one of several or list elements and optionally additional items not listed. In contrast, the expressly referring term "only", eg, "only one of," "exactly one of," or, when used in a claim, "consisting of," means several or exactly one of the elements of the list. will refer to including the elements of In general, when the term "or" as used herein is used before an exclusive term such as, for example, "one of", "one of", "only one of", or "exactly one of", It shall only be construed to mean an exclusive alternative (ie, one or the other, but not both). When used in the claims, "consisting essentially of" has its ordinary meaning in the field of patent law.

As used herein in the specification and claims, the phrase “one or more” in reference to a list of one or more elements means, but not necessarily, one or more elements selected from one or more of the elements in the list of elements; It is to be understood that the list of elements does not exclude any combination of elements, but includes all elements specifically recited in the list of elements and one or more of each element. The above definition also permits that elements may optionally be present other than those specifically identified in the list of elements to which the phrase "one or more" refers, with or without related to the specifically identified elements. Thus, by way of non-limiting example, “one or more of A and B” (or equivalently, “one or more of A or B”, or equivalently, “one of A and/or B”) means that an implementation In an aspect, it refers to one or more As, optionally including more than one, with no B present (optionally including elements other than B); in another embodiment, refers to one or more Bs, optionally including more than one, with no A present (optionally including elements other than A); in another embodiment, one or more A, optionally including more than one, and one or more B, optionally including more than one, optionally including other elements.

In the claims as well as the foregoing specification, all transitional phrases such as "comprising", "including", "accompanying", "having", "comprising", "including", "having", etc. ) is to be understood in an open-ended, ie, inclusive, but not limiting thereof. Conversion phrases such as "consisting essentially of" and "consisting essentially of" may be closed or semi-closed phrases, respectively, as described in section 2111.03. of the Patent Examination Guidelines of the United States Patent and Trademark Office.

Claims (44)

a first electrode comprising lithium as an electroactive material;
a second electrode; and
Composite positioned between the first electrode and the second electrode
As an electrochemical cell comprising a,
The complex is
a separator comprising pores having an average pore size and having a bulk electronic resistivity of at least ^{10 4 Ohm-meters;} and
Ion conductor layer bonded to the separator
including,
the ion conductor layer has a lithium-ion conductivity of ^{at least 10 -6 S/cm,}
wherein the ion conductor layer comprises lithium oxysulfide having an oxide content of 0.1 to 20% by weight, and/or wherein the ion conductor layer contains an oxygen atom to a sulfur atom (O:S) in the range of 0.001:1 to 1.5:1. An electrochemical cell comprising lithium oxysulfide having a ratio. The method of claim 1,
wherein the lithium oxysulfide has an atomic ratio of oxygen atoms to sulfur atoms (O:S) in the range of 0.01:1 to 0.25:1. The method of claim 1,
wherein the ion conductor layer comprising lithium oxysulfide is part of a multilayered structure comprising more than one ion conductor layer. 4. The method of claim 3,
wherein at least two layers of the multilayered structure are formed of different materials. 4. The method of claim 3,
wherein at least two layers of the multilayered structure are formed of the same material. The method of claim 1,
wherein the ion conductor layer comprising lithium oxysulfide is in direct contact with the first electrode and the separator, respectively. The method of claim 1,
wherein the separator has a thickness of 5 microns to 40 microns. The method of claim 1,
wherein the separator has a bulk electronic resistivity of at least ^{10 10 Ohm-meters.} The method of claim 1,
wherein the separator has a bulk electronic resistivity of ^{10 10} Ohm-meter to 10 ^{15 Ohm-meter.} The method of claim 1,
The electrochemical cell of claim 1, wherein the separator is a solid polymer separator. The method of claim 1,
wherein the separator is a solid comprising a mixture of a polymeric binder and a filler comprising a ceramic or glassy/ceramic material. The method of claim 1,
The separator is poly(n-pentene-2), polypropylene, polytetrafluoroethylene, polyamide (eg, polyamide (nylon), poly(ε-caprolactam) (nylon 6), poly(hexamethylene adip) amide) (nylon 66)), polyimides (such as polynitrile, and poly(pyromellitimide-1,4-diphenyl ether) (Kapton®) (NOMEX® registered Trademark)) (KEVLAR(R))), polyether ether ketone (PEEK), and combinations thereof. The method of claim 1,
wherein the composite is formed by treating the surface of the separator with a plasma prior to depositing an ion conductor layer on the surface of the separator. The method of claim 1,
The lithium oxysulfide has the formula x(yLi ₂ S+zLi ₂ O)+MS ₂ (wherein M is Si, Ge, or Sn), wherein y+z=1 and x is 0.5 to 3 days capable of electrochemical cells. The method of claim 1,
wherein the ion conductor layer comprises a glass-forming additive in the range of 0% to 30% by weight of the ion conductor layer. The method of claim 1,
wherein the ion conductor layer comprises one or more lithium salts. 17. The method of claim 16,
wherein the at least one lithium salt is LiI, LiBr, LiCl, Li ₂ CO ₃ , or Li ₂ SO ₄ . 17. The method of claim 16,
wherein the at least one lithium salt is added to the ion conductor layer in the range of 0 mol % to 50 mol %. The method of claim 1,
wherein the separator has an average pore size of 5 microns or less. The method of claim 1,
wherein the separator has an average pore size of 0.5 microns or less. The method of claim 1,
wherein the ion conductor layer has a thickness of 2 microns or less. The method of claim 1,
and the ion conductor layer has a thickness of 800 nm or less. The method of claim 1,
The electrochemical cell, wherein the composite has a lithium ion conductivity of at least ^{10 -5 S/cm at 25°C.} The method of claim 1,
wherein the ratio of the thickness of the ion conductor layer to the average pore size of the separator is at least 1.1:1. The method of claim 1,
An electrochemical cell, wherein the adhesive strength between the separator and the ion conductor layer is at least 350 N/m. The method of claim 1,
wherein the adhesive strength between the separator and the ion conductor layer passes a tape test according to standard ASTM D3359-02. The method of claim 1,
An electrochemical cell, wherein the first electroactive material comprises lithium metal and/or a lithium alloy. 28. The method of claim 27,
wherein the second electrode comprises sulfur as the second electroactive material. The method of claim 1,
wherein the ion conductor layer is deposited on the separator by an electron beam evaporation method or a sputtering process. a first electrode comprising lithium;
a second electrode comprising sulfur;
a separator arranged between the first electrode and the second electrode; and
a solid ionic conductor in contact with and/or bonded to the separator
An electrochemical cell that is a lithium-sulfur cell comprising:
wherein the solid ionic conductor comprises lithium oxysulfide having an oxide content of 0.1 to 20% by weight, and/or wherein the solid ionic conductor is an oxygen atom to a sulfur atom (O:S) in the range of 0.001:1 to 1.5:1. An electrochemical cell comprising lithium oxysulfide having a ratio. The method of claim 1,
wherein the ion conductor layer has an RMS surface roughness between 0.5 nm and 1 micron. The method of claim 1,
wherein the ion conductor layer has a lithium-ion conductivity of less than 20 S/cm. The method of claim 1,
wherein the ion conductor layer is formed substantially of a non-polymeric material. The method of claim 1,
and a thickness of the ion conductor layer is at least 1.1 times the average pore size of the separator and 20 times or less the average pore size of the separator. delete delete delete delete delete between the first electrode and the second electrode for separating the first and second electrodes of the electrochemical cell and for inhibiting interaction of the electrolyte present in the electrochemical cell with one of the electrodes of the electrochemical cell; As a complex that can be arranged,
The complex is
separator; and
a solid ionic conductor in contact with and/or bonded to the separator
including,
wherein the solid ionic conductor comprises lithium oxysulfide having an oxide content of 0.1 to 20% by weight, and/or wherein the solid ionic conductor is an oxygen atom to a sulfur atom (O:S) in the range of 0.001:1 to 1.5:1. A composite comprising lithium oxysulfide having a ratio. between the first electrode and the second electrode for separating the first and second electrodes of the electrochemical cell and for inhibiting interaction of the electrolyte present in the electrochemical cell with one of the electrodes of the electrochemical cell; As a complex that can be arranged,
The complex is
a separator comprising pores having an average pore size and having a bulk electronic resistivity of at least ^{10 4 Ohm-meters;} and
Ion conductor layer bonded to the separator
including,
the ion conductor layer has a lithium-ion conductivity of ^{at least 10 -6 S/cm,}
wherein the ion conductor layer comprises lithium oxysulfide having an oxide content of 0.1 to 20% by weight, and/or wherein the ion conductor layer contains an oxygen atom to a sulfur atom (O:S) in the range of 0.001:1 to 1.5:1. A composite comprising lithium oxysulfide having a ratio. 35. A method for producing an electrochemical cell according to any one of claims 1 to 34, comprising:
manufacturing or providing the separator;
contacting and/or bonding a solid ionic conductor to the separator;
providing further building elements of the electrochemical cell; and
Assembling the electrochemical cell
comprising, a manufacturing method. 43. The method of claim 42,
wherein the step of contacting and/or bonding a solid ionic conductor to the separator is accomplished by depositing an ionic conductor material on a surface of the separator. 43. The method of claim 42,
The method according to claim 1, wherein the intermediate product obtained by contacting and/or bonding a solid ionic conductor to the separator is a composite that is a free-standing structure.

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